"Auto-Parallelization - Automatic parallel map, grep, for, while loops via Rayon work-stealing"

Given any kind of "for" loop, how can it know that there is no synchronization required ? That no mutual exclusion is required ? No concurrent access of some kind ? Offloading some work to another process/thread is expensive, too

If the inner body of the loop is a pure-function, then that's easy (except for the performance part, which may require heuristics or something). But if the body is not pure .. ? I cannot see how this can work reliably with any random code